In many present day automobiles, a timing belt has the vital functions of operating the camshaft controlling the intake and exhaust valves in synchronicity with the ignition and fuel injection systems. The advancements in design and materials for the modern car have brought better performance, lower fuel consumption, and lessened air pollution, all of which come at a price of necessarily improved reliability and precision of all components.
One of the components of the modern engine, the timing belt, which operates the camshaft and ignition components, is a most critical and yet one of the most vulnerable components, since it is composed of fiber reinforced high polymer elastomer, an organic structure in a high temperature stressful environment. A failure of the timing belt can be catastrophic, destroying the whole engine, and to the end of preventing or delaying this failure, much research and development has gone into providing a durable combination of reinforcing fiber and elastomer.
In spite of these efforts, timing belts still fail, usually at the most inopportune times and places in which the engine has been overstressed e.g. in a desert with its high temperature.
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